Research On Design Method Of Prestressed Concrete Box Girder With Corrugated Steel Webs

Prestressed concrete box girder with corrugated steel webs is a new type of steel-prestressed concrete composite structure bridge. It reduces the self-weight that corrugated steel webs are used to replace the traditional concrete web. It has reasonable mechanic property, improves material utilization, shortens construction period, and beatifies the shape. Comparing with traditional prestressed concrete box girder, the prestressed concrete box girder with corrugated steel webs has superiority economy benefit and social benefit. This paper reseaches the design method of prestressed concrete box girder with corrugated steel webs combined with the structure and mechanic properties.Based on the axial mechanical characteristics, and the experience formula of flange effective width and the ultimate stress calculation method of external prestressing tendons, the basic formula of ultimate capacity of the prestressed concrete box-girder bridge with corrugated steel webs was deduced based on the beam flexure theory.Results from many shear strength tests conducted on girder specimens with corrugated webs are available in the literature wherein both local and global shear buckling modes have been observed. The shear resistant design method of structures with corrugated webs was studied. The calculation method of shear stiffness and the checking computations of shear stress were developed.On the basis of design theory for box girder and combined with the structural and mechanic properties of the PC box girder with corrugated steel webs, the Second Theory of A.A.Umanskii was adopted to research on its restrained torsion.The deflection of prestressed concrete box girder with corrugated steel webs can not be ignored when considering Shear deformation. The formula of shearing stress of corrugated steel web was presented considering the action of eccentric loads. Using the Timoshenko theories of beam, the flexural formula of box-girder bridge with corrugated steel webs was deduced in view of the influence of shearing deformation.In the structural design of prestressed concrete box girder with corrugated steel webs, it is pirotal to design how to connect corrugated steel webs to concrect slabs. Through the statistical analysis of the types of connectors of prestressed concrete box girder with corrugated steel webs. We present design calculation and checking methods of several common connectors between corrugated steel webs and concrete slabs.The design and calculational method of prestressed concrete box girder with corrugated steel webs is presented. Its specific design problems are calculation of Section stiffness and checking computations of bending monment, shear and deformation.